高温油藏条件下聚丙烯酰胺水解反应研究  

Study on the hydrolysis of polyacrylamides at high reservoir temperature conditions.

作　　者：孔柏岭[1] 罗九明[1] 

机构地区：[1]河南石油勘探局勘探开发研究院

出　　处：《石油勘探与开发》1998年第6期67-69,共3页Petroleum Exploration and Development

摘　　要：高温条件下，水解作用是影响部分水解聚丙烯酰胺（ＨＰＡＭ）溶液热稳定性的重要因素。河南油田在高温（７５℃）油藏已开展较大规模的聚合物驱矿场试验。用淀粉碘化铬方法，测量该油田产出水（污水）中３种水解度的高分子量ＨＰＡＭ的水解度，以研究７５℃条件下不同水解度的ＨＰＡＭ样品在污水中的水解过程和水解反应机理。根据试验结果，给出了水解度与老化时间的关系式和水解速度与老化时间的关系式，３种ＨＰＡＭ的这２种关系式基本一致，表明ＨＰＡＭ在污水中的水解度（最大为７５％）均随老化时间的增加而快速大幅度增大；水解速度与老化时间的二次方成反比关系，并且３种ＨＰＡＭ的水解速率和水解度之间的关系可以用同一个关系式表达。该关系式说明，在７５℃的温度条件下，ＨＰＡＭ的水解速度仅由水解度决定，而与ＨＰＡＭ的分子量无关，呈现出典型的自阻滞水解反应机理。根据得出的３种ＨＰＡＭ的水解度、水解速度各自与老化时间的关系式，可以预测各种ＨＰＡＭ在老化期间任一时刻的水解速度和水解度值。我国大部分油田地层水属弱碱性，ＨＰＡＭ溶液在这类污水中的水解反应速度很快，稳定性变差，因此在选择聚合物和水质时，应充分考虑高温水解作用的影响。图２表２参１１（郭海莉摘）The field test of polymerflooding on a large scale has been made at high reservoir temperature (75℃) in Henan oil field. The hydrolysis of polyacrylamide (HPAM) is an important factor that affects the thermal stability of HPAM solution at high temperature. In order to investigate the hydrolysis process and mechanism of three different hydrolysis degree of HPAM samples in oilfield produced water at 75℃, the starch triiodide method is used to determine the hydrolysis degree of HPAM during aging time. The experimental results show that the hydrolysis degree is increased obviously with aging time and the hydrolysis rate is inverse proportion to square of aging time. The hydrolysis rate of three HPAM samples is only dependent on the hydrolysis degree and not dependent on the molecular weight of HPAM. The mechanism of hydrolysis reaction obeys an autoreterded kinetics and the maximum value of hydrolysis degree of HPAM is 75% in oilfield produced water at 75℃. The equations of relation between hydrolysis degree and aging time and of relation between hydrolysis rate and aging time are also established, so the values of hydrolysis rate and hydrolysis degree at any aging time can be estimated by using these equations. The most formation waters in our country belong to weak alkaline, HPAM will hydrolyze rapidly in this type of water, and the thermal stability and viscosity of HPAM solution will decrease obviously. The effect of hydrolysis of HPAM on the properties of HPAM solution must be taken into account when the types of HPAM and water are selected.

关 键 词：油藏 聚丙烯胺 水解反应 聚合物驱油 

分 类 号：TE351.46[石油与天然气工程—油气田开发工程]